The present invention is directed to bicyclic compounds that are inhibitors of mammalian Target Of Rapamycin (mTOR) kinase (also known as FRAP, RAFT, RAPT, SEP). In particular, the present invention is directed to fused bicyclic compounds that are mTOR inhibitors useful in the treatment of cancer.
It has been shown that high levels of dysregulated mTOR activity are associated with a variety of human cancers and several hamartoma syndromes, including tuberous sclerosis complex, the PTEN-related hamartoma syndromes and Peutz-Jeghers syndrome. Although rapamycin analogues are in clinical development for cancer as mTOR kinase inhibitors, the clinical out come with CCI-779 is just modest in breast and renal cancer patients. This is probably because rapamycin partially inhibits mTOR function through raptor-mTOR complex (mTORC1). It has been also found that ⅔ of the breast cancer and ½ of renal cancer patients are resistant to rapamycin therapy. With a recent discovery of rictor-mTOR complex (mTORC2) which is involved in phosphorylation of AKT (S473) that is important in regulation of cell survival and modulation of PKCα that plays a major role in regulation of actin cytoskeletal organization in a rapamycin-independent manner, and inhibition of these activities of mTOR is probably important for broader antitumor activity and better efficacy. Therefore, it is desirable to develop novel compounds that are direct inhibitors of mTOR kinase, which would inhibit mTORC1 and mTORC2.
With the recent discovery of rapamycin independent function of mTOR (by mTOR2) in phosphorylation AKT (at S473) that is important in regulation of cell survival and modulation of PKCα, which plays a major role in regulation of actin cytoskeletal organization, it is believed that inhibition of mTOR function by rapamycin is partial. Therefore, discovery of a direct mTOR kinase inhibitor, which would completely inhibit the function of both mTORC1 and mTORC2, is required for broader anti-tumor activity and better efficacy. Here we describe the discovery of direct mTOR kinase inhibitors, which can be used in the treatment of a variety of cancers—including breast, lung, kidney, prostate, blood, liver, ovarian, thyroid, GI tract and lymphoma—and other indications such as rheumatoid arthritis, hamartoma syndromes, transplant rejection IBD, multiple sclerosis and immunosuppression.
Recent success of Tarceva, an EGFR kinase inhibitor for the treatment of NSCLC, and prior success with Gleevec for the treatment of CML indicate that it is possible to develop selective kinase inhibitors for the effective treatment of cancers. Although there are several anti-cancer agents including kinase inhibitors, there is still continuing need for improved anti-cancer drugs, and it would be desirable to develop new compounds with better selectivity, potency or with reduced toxicity or side effects. Thus, it is desirable to develop compounds that exhibit mTOR inhibition in order to treat cancer patients. Further, such compounds may be active in other kinases such as, for example, PI3K, Src, KDR, to add efficacy in breast, non-small cell lung cancer (NSCLC), renal cell carcinoma, mantle cell lymphoma, endometrial cancers, or other hamartoma syndromes.
With respect to new salt forms, it is desirable, that they provide a favorable profile with respect to pharmaceutical manufacture, formulation, storage, and use. For example, it is desirable; that the salt exhibit favorable solubility, hygroscopicity, stability, uniformity, reproducibility, purity, among other known criteria.
US2007/0112005 discloses, inter alia, mTOR inhibiting compounds. The present invention relates to particular salts and forms of mTOR inhibitor compounds, their preparation, formulation, and use.